It’s fun to spend time outdoors now that the weather is nicer. But you know what’s not so fun? Getting eaten alive by mosquitoes. Those evil little suckers can do a number to your arms, legs, or any area that’s exposed. Sometimes, it can get so bad that you’d probably rather suffer through a heat wave wearing long-sleeved shirts and jeans to avoid getting bitten, right? If you’ve ever wondered why you’re in itchy hell while your friends are perfectly fine, you’re not alone. There are lots of misconceptions (and downright adorable myths floating around out there) for why some people are more susceptible to bug bites than others, but Elizabeth Tanzi, M.D., a dermatologist in Washington, D.C., sets the record straight.

Research suggests that the primary cause of your susceptibility is, yes, blood type, says Tanzi. “We still don’t completely understand why or what the issue is with the blood type,” she says. “But it’s typically type O blood that attracts them.”

Your blood isn’t the only thing making you suffer, though. “There are two things at play here,” says Tanzi. “It’s also the fact that some people’s skin reacts more vividly than others.” If you have more sensitive skin, a bug bite could trigger the release of inflammatory cells to the area, similar to the reaction of hives. “When those people get a bite, they can have a tremendous amount of swelling,” she says, resulting in those attractive red welts. So while some people actually do get bitten more than others, some people just notice bites more because their skin reacts more.

If you’re one of those people who get inflamed easily, you can prepare for battle with the little buzzers with some antihistamines in addition to your bug spray. “Start taking them a couple days before you are exposed to avoid the swelling,” says Tanzi. “The histamines will stabilize in your system, and you won’t have the same wild reaction.” So if you have a cookout, picnic, or other outdoor event coming up, consider popping some over-the-counter allergy meds like Claritin or Zyrtec for a few days beforehand and then on the day of, as well.

The biological explanation may be a bit less fun than some of those old wives’ tales. There isn’t real evidence that wearing certain colors of clothing or wearing floral perfumes makes you more attractive to mosquitoes. As for diet, “People say, ‘Oh, if you’re eating a lot of sweets, you’ll get them,’” says Tanzi. “But scientists don’t know if it’s diet-related.”A study in the Journal of the American Mosquito Control Association found that mosquitos preferred landing on the arms of the study subjects after they had imbibed 350 milliliters of beer. But it’s worth pointing out that the study was small (only 13 participants)—and Tanzi says she hasn’t heard any evidence that drinking beer ups your odds of getting bitten.

They do know, however, that some scents and oils repel them, so stock up on those citronella candles. Also, consider your environment: “Wet, steamy climates are the worst for mosquitos and gnats, especially toward the end of the day,” says Tanzi. “Wooded areas are bad, or grassy beaches where there could be sand fleas.”

And if you still get hit with one of those little red bumps, there is advice to deal with it, whether you are prone to them or not: Don’t scratch. “By scratching, you cause more trauma to the area, which causes more swelling,” says Tanzi. Sit on your hands if you’ve got to, but you’re just making it worse by picking or scratching.